Error When Export datetime string format to excel

Shirley

HI,
I meet an problem when I Export datetime string format to Excel. I am using the "ExportFormat.ExcelML". The date type of datetime is string, when I export it to excel,it convert to False. So I think it's the problem of data type. If the type is "datetime", it will be ok.
So how should I handle this problem, export the datetime string to excel?
Thanks for your help in advance.
Shirley

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